Thermo-developable light-sensitive diazo compositions and elements



United States Patent "ic 3,386,827

Patented June 4, 1968 (b) 3,386,827 II II THERMO-DEVELOPABLE LIGHT-SENSITIVE and DIAZO COMPOSKTIONS AND ELEMENTS d Claude M. Aebi, Endicott, and Harry F. Herbrandson, 5

Schenectady, N.Y., assignors to International Business h Machines Corporation, New York, N.Y., a corporan,= 0 0H and R,= N

wg fiimz fgg Al 17 1964 sen No. 390 240 In all other cases, the compounds act primarily as 4 Claim; i coupler formers or generators when heated.

10 The temperature at which the present compounds re- The present invention relates to light-sensitive diazoact to fuhctloh as P modlfiers and/01' P type compositions which are developable by heat. The rS vanes, depending on the nature of the substituents, present invention also relates to light-sensitive diazotype but generally 15 1n the range of from about to elements, such as films or copying papers which comprise about 200 self-supporting films of the compositions or a suitable 15 The eSSeI1ha1 1 ngr6d -1eht$ 0f m6 P E COmPOSIUOHS substrate coated on at least part of one surface with the are a hght'sehsltlve dfazohlum Salt mlxture of Salts Present compositions and a compound or mixture of compounds selected from Thermo-developable, light-sensitive diazotype composithe group havlhg the fOnOWlhg gfinefal formula: tions and elements are well known and are of various 0R types. Some contain acid stabilizers which are decomposed I R OH -C-CHR by heat to alter the pH of the system. Others contam com- 1 a 2 pounds which decompose upon heating to form a base, 4 thus also altering the pH of the system to a level at which Where radicals R through R are groups of the type dethe color-forming reaction may proceed between the lightscribed above. sensitive salt and a coupling component present in the The essential ingredients are ordinarily combined in a composition. Still other thermo-developable systems consolution of a film-forming resin in a volatile solvent and tain compounds which decompose upon heating to proare applied as a coating onto a suitable substrate. Selfduce coupling components in situ for reaction with the supporting elements may also be produced by co the light-sensitive diazonium salt. composition on a temporary support, drying and then The present invention relates to new light-sensitive stripping off the film. diazotype compositions and elements comprising com- While the exact proportions of ingredients are not critipounds of a class which may serve as pH modifiers and/or cal, good results are Obtained y Combi ing the ingredicoupler generators. The compounds present in the coments in the following general proportions: position of this invention are any of those having the 3 Ingredient: Percent by Weight followmg formula- 0 Light-sensitive diazonium salt 0.2-6.0 0R See footnote 1.0-20.0 Film-forming natural or synthetic resin 5.040.0 Ra Volatile solvent for resin Balance where R and R may be any radical selected from the 40 group consisting of *Ri-oH -(lJ-(lln-R,

O O Ra R4 CN, -(INHR and -(U}-OR7 For optimum results, up to a few percent of various and Wham R3, R4 R5, R6 and R7 may be any radical other additives, such as a stabilizing acid, cyanoguanidine, lected from the group consisting of -H, a substituted or 21116 'chlonde: thlourea and other base flouplel' unsubstituted alkyl group having from 1 to 8 carbon eratorsr may also be added to P atoms in the chain and a substituted or unsubstituted aryl A prqferrsdfiormulatwn of a F F FY hght'sehslhve group composition in accordance with this invention is as The compounds of the present invention act as both follows: coupler generators and pH modifiers under the following I di t; Percent b weight con i i Light-sensitive diazoniurn Salt 05-5 (1) Wh r R1 n 2 both are See footnote 3-20 0 Zinc chloride 0-1 & R7 Thiourea 0-2 Cyanoguanidine 0-5 and R is hydrogen, and

Stabilizing acid 0-5 Where elthel 1 2 15 Film-forming natural or synthetic resin 5-15 Fl) Volatile solvent for resin Balance I -COH and the other group is II n R3 4 -oN, -oNHRu or COR Where and R5 is an alkyl group having Among the coupler generator and/orpH modifier comfmm 1 to 8 carbon atoms in the chain, the compounds pounds suitable for use in the present invention, the folare predominantly pH modifiers where the other sublowing are typlcal: stituents are as follows: 1. f) (|)H (I) (a) HO-(l-CH -(f-CH- -OH The coupler generator and/or pH modifier compounds may be prepared according to methods well known in the F prior art. For example, the compound represented by formula number 8 above, namely, 3 hydroxyglutaronitrile, may be prepared according to the method disclosed by F. Johnson et al., J. Org. Chem, volume 27, pages 2241-3 (1962). The compound represented by formula namely, B-hydroxy-B-methyl glutaric acid may be prepared according to the method disclosed by Thorne et al., Biochem. Biophys. Acta, volume 59, pages 273-279 (1912) and Wright, Gen. Comp. Endocrinol, volume 1,

Under the influence of heat, certain of the present com- 5 pounds generate a component capable of coupling with a ht-sensitive d-iazonium salt. It is believed that the coupling component is produced by splitting out water, an

cohol or a phenol formed by radical R 0 and a hydrogen from the carbon to which R; is attached. If R; is H,

50 loss of water may occur in either direction de pending on Where R is hydrogen, the by- /2 zinc chloride, p-diazo-2,5-dimethoxy-l-p-toluyl-mercapto benzene A zinc chloride, 2,5,4-triethoxy-diphenyl- 4-di-azonium oxalate, etc.

The following examples will assist towards a full understanding of the present invention. While the examples are not intended to be limiting, they do serve to illustrate certain preferred embodiments of the invention.

Example 1 A 100 ml. solution is prepared which has the following composition:

Ingredient: Percent by weight p-Diazodimethylaniliue, full zinc chloride 1 See footnote Polyvinylbutyral resin l0 Methanol to make up 100 m1. of solution Balance The solution is coated on a transparent polyethylene terephthalate substrate and is dried in air for 24 hours. The resulting element is exposed to light through a negative and is then developed by heating with infra-red radiation for 60 seconds at a temperature of 150 C.

Example 2.

A 100 ml. solution having the following composition is prepared: Ingredient: Percent by weight p-Diazodiethylanil'ine, full zinc chloride 6.0 See footnote 20.0 Thiourea 2.0 Citric acid 3.0 Zinc chloride 1.0 Cellulose acetate butyrate 15.0 Acetone, methyl ethyl ketone and methanol,

ratio 1:1:1 to make 100 ml. solution Balance 0 OH O *HjN- -CHQ(:3?H- NH| The solution is coated, dried, exposed and developed following the procedure of Example 1, except that the temperature of development is 180 C.

Example 3 A 100 ml. solution having the following composition is prepared:

Ingredient: Percent by weight p-Diazo-Z,5-diethoxy benzoyl aniline, /2. zinc chloride 3.0 See footnote 10. Tartaric acid 1.5 Thiourea 0.5 Zinc chloride 0.5 Cyanoguanidine 2.0 Polyvinylbutyral resin 20.0 Methanol to make 100 m1. of solution Balance NC-CH1-CCH-CN 01H; CH;

The solution is coated, dried, exposed and developed as in Example 1.

6 Example 4 A ml. solution having the following composition is prepared:

Ingredient: Percent by weight p-Diazo-l-morpholino benzene, A zinc chloride 5.0 See footnote 15.0 Thiourea 1.0 Tartaric acid 2.5 Zinc chloride 0.2 Celulose acetate 20.0

Acetone, methyl ethyl :ketone and methanol,

ratio 1: 1:1 to make 100 ml. of solution Balance The solution is coated, dried, exposed and developed as in Example 1.

Example 5 A 100 ml. solution having the following composition is prepared:

I H; on;

The solution is coated, dried, exposed and developed as 'in Example 1.

Example 6 A 100 ml. solution having the following composition is prepared:

Ingredient: Percent by weight p-Diazo-dimethylaniline, full zinc chloride 3.0 See footnote 10.0 Thiourea 1.0 Citraconic acid 5.0 Zinc chloride 0.4 Polyvinylbutyral 15.0 Methanol to make 100 ml. solution Balance The solution is coated, dried, exposed and developed as in Example 1.

Where the specific compound of the invention is primarily a coupler generator, it will be necessary to add a base generator to the composition. In Examples 3 and 5, for instance, cyanoguanidine and thiourea perform this function.

The compositions of the invention are highly useful in producing all types of light-sensitive, thermo-developable element, such as copy papers, films and the like, which can be developed solely by the application of heat.

It will be understood by those skilled in the art that various modifications may be made in the invention as described and illustrated in the preceding examples without departing from the scope or spirit of the invention as expressed in the following claims.

What is claimed is:

1. A light-sensitive, thermo-developable compositio comprising a light-sensitive diazonium compound and a compound having the following general formula:

R5 Rr-oHr-ii-oH-R where R and R are radicals selected from the group consisting of 0 -CN and --i J-NHRa and where R R R and R are radicals selected from the group consisting of -H, an alkyl group having from 1 to 8 carbon atoms in the chain, and an aryl group.

2. A light-sensitive, thermo-developable composition comprising:

from 0.2% to 6.0% by weight of a light-sensitive diazonium compound, from 1.0% to 20.0% by weight of a compound having the following general formula:

where R and R are radicals selected from the group consisting of -CN and i l-NEE;

and where R R R and R are radicals selected from the group consisting of H, an alkyl group having from 1 to 8 carbon atoms in the chain, and an aryl group,

from 5.0% to 40.0% by weight of a film-forming resin, and the balance a volatile solvent for said resin.

3. A light-sensitive, thermo-developable element comprising a substrate and a coating on at least part of the surface of said substrate, said coating comprising the residue of the composition of claim 2 after evaporation of said volatile solvent.

4. A light-sensitive, thermo-developable element comprising a self-supporting film comprising the residue of the composition of claim 2 after evaporation of said solvent.

References Cited UNITED STATES PATENTS 3,164,468 1/ 1965 Moskowitz et a1. 9649 3,303,028 2/1967 Aebi et a1. 96-49 X 3,307,952 3/1967 Aebi et a1. 96-49 X NORMAN G. TORCHIN, Primary Examiner.

C. BOWERS, Assistant Examiner. 

1. A LIGHT-SENSITIVE, THERMO-DEVELOPABLE COMPOSITION COMPRISING A LIGHT-SENSITIVE DIAZONIUM COMPOUND AND A COMPOUND HAVING THE FOLLOWING GENERAL FORMULA: 